Buy article online - an online subscription or single-article purchase is required to access this article.
Download citation
Download citation
link to html
In the title compound, [Cu2(C2H3O2)2(C20H36N8)(H2O)2](C2H3O2)2·6H2O, the dinuclear cation has inversion symmetry and contains square-pyramidal CuII ions separated by 7.471 (1) Å. Symmetry-related cations are linked to a framework of rings of five water molecules, where each water molecule acts as both a single hydrogen-bond donor and acceptor, an arrangement very close to that believed to exist in liquid water.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536805000206/hb6133sup1.cif
Contains datablocks I, global

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S1600536805000206/hb6133Isup2.hkl
Contains datablock I

CCDC reference: 263544

Key indicators

  • Single-crystal X-ray study
  • T = 296 K
  • Mean [sigma](C-C) = 0.003 Å
  • R factor = 0.032
  • wR factor = 0.093
  • Data-to-parameter ratio = 20.8

checkCIF/PLATON results

No syntax errors found



Alert level A PLAT052_ALERT_1_A (Proper) Absorption Correction Method Missing .. ?
Alert level C PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ .... ? PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent ..... ? PLAT220_ALERT_2_C Large Non-Solvent C Ueq(max)/Ueq(min) ... 2.69 Ratio PLAT222_ALERT_3_C Large Non-Solvent H Ueq(max)/Ueq(min) ... 3.23 Ratio PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X) Cu1 - O15 .. 6.08 su PLAT244_ALERT_4_C Low 'Solvent' Ueq as Compared to Neighbors for C20 PLAT354_ALERT_3_C Short O-H Bond (0.82A) O24 - H241 ... 0.68 Ang. PLAT354_ALERT_3_C Short O-H Bond (0.82A) O26 - H261 ... 0.71 Ang. PLAT380_ALERT_4_C Check Incorrectly? Oriented X(sp2)-Methyl Moiety C13 PLAT380_ALERT_4_C Check Incorrectly? Oriented X(sp2)-Methyl Moiety C19 PLAT380_ALERT_4_C Check Incorrectly? Oriented X(sp2)-Methyl Moiety C21 PLAT480_ALERT_4_C Long H...A H-Bond Reported H152 .. O16 .. 2.78 Ang. PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd. # 2 C2 H3 O2 PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd. # 3 H2 O PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd. # 4 H2 O PLAT790_ALERT_4_C Centre of Gravity not Within Unit Cell: Resd. # 5 H2 O
1 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 16 ALERT level C = Check and explain 0 ALERT level G = General alerts; check 3 ALERT type 1 CIF construction/syntax error, inconsistent or missing data 2 ALERT type 2 Indicator that the structure model may be wrong or deficient 3 ALERT type 3 Indicator that the structure quality may be low 9 ALERT type 4 Improvement, methodology, query or suggestion

Computing details top

Data collection: XSCANS (Siemens, 1996); cell refinement: XSCANS; data reduction: XSCANS; program(s) used to solve structure: SHELXTL-Plus (Sheldrick, 1998); program(s) used to refine structure: SHELXTL-Plus; molecular graphics: SHELXTL-Plus and Mercury (CCDC, 2004); software used to prepare material for publication: SHELXTL-Plus.

[µ-2,8-Dimethyl-5,11-bis(dimethylaminoethyl)-1,4,5,6,7,10,11,12- octahydrodiimidazo[4,5 - h;4,5 - c][1,6]diazecine]bis[aquacopper(II)] diacetate hexahydrate top
Crystal data top
[Cu2(C2H3O2)2(C20H36N8)(H2O)2](C2H3O2)2·6H2OF(000) = 1896
Mr = 895.95Dx = 1.416 Mg m3
Monoclinic, C2/cMo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2ycCell parameters from 75 reflections
a = 23.562 (3) Åθ = 4.1–13.8°
b = 6.5271 (5) ŵ = 1.09 mm1
c = 28.881 (4) ÅT = 296 K
β = 108.863 (10)°Irregular lump, blue
V = 4203.1 (8) Å30.50 × 0.48 × 0.40 mm
Z = 4
Data collection top
Bruker P4
diffractometer
4720 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube, FN4Rint = 0.026
Graphite monochromatorθmax = 29.0°, θmin = 1.8°
2θ/ω scansh = 321
Absorption correction: ψ scan
(XSCANS; Siemens, 1996)
k = 88
Tmin = 0.597, Tmax = 0.646l = 3739
11427 measured reflections3 standard reflections every 97 reflections
5582 independent reflections intensity decay: 1%
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: difmap (O-H) and geom (others)
R[F2 > 2σ(F2)] = 0.032H atoms treated by a mixture of independent and constrained refinement
wR(F2) = 0.093 w = 1/[σ2(Fo2) + (0.0522P)2 + 2.3286P]
where P = (Fo2 + 2Fc2)/3
S = 1.02(Δ/σ)max = 0.003
5582 reflectionsΔρmax = 0.42 e Å3
269 parametersΔρmin = 0.40 e Å3
0 restraintsExtinction correction: SHELXTL-Plus (Sheldrick, 1998), Fc*=kFc[1+0.001xFc2λ3/sin(2θ)]-1/4
Primary atom site location: structure-invariant direct methodsExtinction coefficient: 0.0045 (2)
Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
xyzUiso*/Ueq
Cu10.867648 (8)0.21276 (3)0.122730 (6)0.02627 (8)
N10.83590 (6)0.5662 (2)0.00324 (5)0.0296 (3)
H1A0.84360.62990.02660.036*
C20.87673 (7)0.5015 (3)0.03858 (6)0.0305 (3)
N30.84956 (6)0.4116 (2)0.06704 (5)0.0278 (3)
C40.78868 (7)0.4193 (2)0.04169 (5)0.0246 (3)
C50.77913 (7)0.5127 (2)0.00241 (6)0.0263 (3)
C60.74920 (7)0.3194 (2)0.06621 (6)0.0256 (3)
H6A0.70960.29510.04300.031*
H6B0.74530.40480.09250.031*
N70.77908 (6)0.1214 (2)0.08590 (4)0.0247 (3)
C80.75524 (8)0.0276 (3)0.12289 (6)0.0335 (3)
H8A0.72200.06290.10690.040*
H8B0.74100.13360.13990.040*
C90.80528 (9)0.0918 (3)0.15866 (7)0.0406 (4)
H9A0.79200.14280.18500.049*
H9B0.81570.20840.14220.049*
N100.85876 (7)0.0411 (3)0.17909 (5)0.0358 (3)
C110.91174 (11)0.0893 (5)0.20261 (10)0.0665 (7)
H11A0.90510.16620.22870.100*
H11B0.94650.00430.21550.100*
H11C0.91790.18180.17880.100*
C120.84944 (11)0.1843 (4)0.21583 (8)0.0571 (6)
H12A0.84510.10770.24290.086*
H12B0.81380.26360.20110.086*
H12C0.88330.27430.22730.086*
C130.94247 (8)0.5242 (3)0.04911 (7)0.0418 (4)
H13A0.96320.46810.08080.063*
H13B0.95230.66670.04860.063*
H13C0.95440.45230.02470.063*
C140.72276 (7)0.5260 (2)0.04508 (6)0.0271 (3)
H14A0.71850.66460.05790.033*
H14B0.68890.49850.03390.033*
O150.92126 (7)0.0142 (2)0.09740 (6)0.0413 (3)
H1510.9189 (13)0.010 (4)0.0703 (11)0.062*
H1520.9578 (14)0.039 (4)0.1137 (10)0.062*
O160.93534 (5)0.3720 (2)0.16520 (5)0.0398 (3)
C170.99060 (8)0.3602 (3)0.16923 (6)0.0366 (4)
O181.01440 (7)0.2130 (2)0.15518 (6)0.0512 (4)
C191.02870 (9)0.5418 (4)0.19276 (10)0.0573 (6)
H19A1.06940.51820.19410.086*
H19B1.02720.56000.22530.086*
H19C1.01370.66260.17380.086*
C201.10527 (8)0.0234 (3)0.04221 (7)0.0393 (4)
C211.07823 (19)0.1185 (5)0.07090 (12)0.0912 (12)
H21A1.06050.23430.05100.137*
H21B1.04800.04640.08010.137*
H21C1.10910.16470.09980.137*
O221.10294 (8)0.0273 (3)0.00049 (6)0.0587 (4)
O231.13040 (8)0.1833 (2)0.06343 (5)0.0495 (4)
O241.13259 (7)0.2679 (3)0.15580 (6)0.0479 (4)
H2411.1301 (16)0.256 (5)0.1318 (12)0.072*
H2421.0965 (16)0.248 (5)0.1551 (12)0.072*
O251.21858 (9)0.0448 (3)0.19016 (8)0.0661 (5)
H2511.1933 (18)0.037 (6)0.1827 (14)0.099*
H2521.2425 (18)0.003 (6)0.2164 (14)0.099*
O261.19357 (10)0.5739 (4)0.22408 (7)0.0716 (6)
H2611.1774 (19)0.510 (7)0.2042 (15)0.107*
H2621.1959 (19)0.678 (7)0.2089 (15)0.107*
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
Cu10.02392 (11)0.02850 (12)0.02496 (11)0.00028 (7)0.00594 (7)0.00114 (7)
N10.0325 (7)0.0276 (6)0.0289 (6)0.0082 (5)0.0100 (5)0.0003 (5)
C20.0299 (7)0.0277 (8)0.0329 (8)0.0067 (6)0.0087 (6)0.0024 (6)
N30.0266 (6)0.0263 (6)0.0287 (6)0.0045 (5)0.0065 (5)0.0014 (5)
C40.0268 (7)0.0196 (6)0.0260 (7)0.0029 (5)0.0064 (5)0.0040 (5)
C50.0296 (7)0.0206 (7)0.0281 (7)0.0043 (6)0.0084 (6)0.0029 (5)
C60.0264 (7)0.0232 (7)0.0266 (7)0.0005 (5)0.0080 (6)0.0024 (5)
N70.0262 (6)0.0239 (6)0.0239 (6)0.0031 (5)0.0082 (5)0.0001 (5)
C80.0326 (8)0.0391 (9)0.0302 (8)0.0083 (7)0.0120 (7)0.0033 (7)
C90.0469 (10)0.0399 (9)0.0341 (9)0.0020 (8)0.0121 (8)0.0094 (7)
N100.0330 (7)0.0450 (9)0.0279 (7)0.0044 (6)0.0076 (6)0.0055 (6)
C110.0470 (12)0.0806 (19)0.0647 (15)0.0202 (12)0.0081 (11)0.0369 (14)
C120.0545 (13)0.0834 (18)0.0373 (10)0.0145 (12)0.0206 (10)0.0184 (10)
C130.0306 (8)0.0472 (11)0.0471 (10)0.0101 (8)0.0118 (8)0.0018 (8)
C140.0311 (7)0.0208 (6)0.0275 (7)0.0009 (6)0.0069 (6)0.0020 (5)
O150.0412 (7)0.0426 (7)0.0416 (7)0.0037 (6)0.0155 (6)0.0074 (6)
O160.0268 (6)0.0498 (8)0.0390 (7)0.0036 (5)0.0057 (5)0.0116 (6)
C170.0273 (8)0.0434 (10)0.0341 (8)0.0001 (7)0.0028 (6)0.0042 (7)
O180.0334 (7)0.0540 (9)0.0641 (10)0.0001 (6)0.0126 (7)0.0163 (7)
C190.0335 (10)0.0546 (13)0.0758 (16)0.0054 (9)0.0066 (10)0.0221 (12)
C200.0365 (9)0.0457 (10)0.0392 (9)0.0071 (8)0.0171 (7)0.0012 (8)
C210.137 (3)0.078 (2)0.086 (2)0.066 (2)0.074 (2)0.0263 (17)
O220.0698 (11)0.0679 (11)0.0423 (8)0.0090 (9)0.0236 (8)0.0099 (7)
O230.0645 (10)0.0496 (8)0.0394 (7)0.0234 (7)0.0236 (7)0.0029 (6)
O240.0389 (7)0.0635 (10)0.0416 (7)0.0031 (7)0.0133 (6)0.0098 (7)
O250.0646 (11)0.0511 (10)0.0716 (12)0.0120 (8)0.0071 (9)0.0070 (9)
O260.0719 (12)0.0731 (13)0.0562 (11)0.0239 (10)0.0019 (9)0.0037 (9)
Geometric parameters (Å, º) top
Cu1—O161.9657 (13)C8—H8A0.9700
Cu1—N32.0026 (14)C8—H8B0.9700
Cu1—N102.0417 (15)C9—H9A0.9700
Cu1—N72.0992 (13)C9—H9B0.9700
Cu1—O152.2186 (14)C11—H11A0.9600
N1—C21.346 (2)C11—H11B0.9600
N1—C51.390 (2)C11—H11C0.9600
C2—N31.330 (2)C12—H12A0.9600
C2—C131.486 (2)C12—H12B0.9600
N3—C41.385 (2)C12—H12C0.9600
C4—C51.364 (2)C13—H13A0.9600
C4—C61.489 (2)C13—H13B0.9600
C5—C141.494 (2)C13—H13C0.9600
C6—N71.493 (2)C14—H14A0.9700
N7—C81.4899 (19)C14—H14B0.9700
N7—C14i1.5113 (19)O15—H1510.77 (3)
C8—C91.509 (3)O15—H1520.91 (3)
C9—N101.486 (3)C19—H19A0.9600
N10—C111.482 (3)C19—H19B0.9600
N10—C121.483 (3)C19—H19C0.9600
C14—N7i1.5113 (19)C21—H21A0.9600
O16—C171.272 (2)C21—H21B0.9600
C17—O181.245 (2)C21—H21C0.9600
C17—C191.509 (3)O24—H2410.68 (3)
C20—O221.234 (2)O24—H2420.85 (3)
C20—O231.257 (2)O25—H2510.78 (4)
C20—C211.514 (3)O25—H2520.83 (4)
N1—H1A0.8600O26—H2610.71 (4)
C6—H6A0.9700O26—H2620.82 (4)
C6—H6B0.9700
O16—Cu1—N394.44 (6)H6A—C6—H6B108.7
O16—Cu1—N1093.69 (6)N7—C8—H8A110.1
N3—Cu1—N10161.07 (6)C9—C8—H8A110.1
O16—Cu1—N7159.97 (5)N7—C8—H8B110.1
N3—Cu1—N781.87 (5)C9—C8—H8B110.1
N10—Cu1—N784.64 (6)H8A—C8—H8B108.4
O16—Cu1—O1597.20 (6)N10—C9—H9A109.6
N3—Cu1—O1599.44 (6)C8—C9—H9A109.6
N10—Cu1—O1596.46 (6)N10—C9—H9B109.6
N7—Cu1—O15102.83 (5)C8—C9—H9B109.6
C2—N1—C5108.58 (13)H9A—C9—H9B108.1
N3—C2—N1110.22 (14)N10—C11—H11A109.5
N3—C2—C13126.54 (16)N10—C11—H11B109.5
N1—C2—C13123.21 (16)H11A—C11—H11B109.5
C2—N3—C4106.31 (13)N10—C11—H11C109.5
C2—N3—Cu1139.65 (12)H11A—C11—H11C109.5
C4—N3—Cu1111.28 (10)H11B—C11—H11C109.5
C5—C4—N3109.85 (13)N10—C12—H12A109.5
C5—C4—C6134.44 (14)N10—C12—H12B109.5
N3—C4—C6115.63 (13)H12A—C12—H12B109.5
C4—C5—N1105.03 (13)N10—C12—H12C109.5
C4—C5—C14129.08 (14)H12A—C12—H12C109.5
N1—C5—C14125.12 (14)H12B—C12—H12C109.5
C4—C6—N7105.66 (12)C2—C13—H13A109.5
C8—N7—C6112.85 (12)C2—C13—H13B109.5
C8—N7—C14i112.04 (12)H13A—C13—H13B109.5
C6—N7—C14i111.25 (11)C2—C13—H13C109.5
C8—N7—Cu1107.27 (9)H13A—C13—H13C109.5
C6—N7—Cu1102.49 (9)H13B—C13—H13C109.5
C14i—N7—Cu1110.43 (9)C5—C14—H14A108.8
N7—C8—C9108.12 (14)N7i—C14—H14A108.8
N10—C9—C8110.18 (15)C5—C14—H14B108.8
C11—N10—C12109.36 (19)N7i—C14—H14B108.8
C11—N10—C9109.10 (18)H14A—C14—H14B107.7
C12—N10—C9110.44 (16)Cu1—O15—H151117 (2)
C11—N10—Cu1113.10 (13)Cu1—O15—H15296.9 (17)
C12—N10—Cu1107.57 (14)H151—O15—H152105 (3)
C9—N10—Cu1107.24 (11)C17—C19—H19A109.5
C5—C14—N7i113.59 (13)C17—C19—H19B109.5
C17—O16—Cu1128.69 (13)H19A—C19—H19B109.5
O18—C17—O16124.97 (18)C17—C19—H19C109.5
O18—C17—C19119.19 (17)H19A—C19—H19C109.5
O16—C17—C19115.84 (18)H19B—C19—H19C109.5
O22—C20—O23124.35 (18)C20—C21—H21A109.5
O22—C20—C21118.5 (2)C20—C21—H21B109.5
O23—C20—C21117.15 (18)H21A—C21—H21B109.5
C2—N1—H1A125.7C20—C21—H21C109.5
C5—N1—H1A125.7H21A—C21—H21C109.5
C4—C6—H6A110.6H21B—C21—H21C109.5
N7—C6—H6A110.6H241—O24—H242102 (3)
C4—C6—H6B110.6H251—O25—H252105 (4)
N7—C6—H6B110.6H261—O26—H26299 (4)
C5—N1—C2—N31.04 (19)N3—Cu1—N7—C635.39 (9)
C5—N1—C2—C13177.03 (16)N10—Cu1—N7—C6131.29 (10)
N1—C2—N3—C40.35 (18)O15—Cu1—N7—C6133.28 (9)
C13—C2—N3—C4177.64 (17)O16—Cu1—N7—C14i163.81 (14)
N1—C2—N3—Cu1158.56 (13)N3—Cu1—N7—C14i83.21 (10)
C13—C2—N3—Cu119.4 (3)N10—Cu1—N7—C14i110.11 (10)
O16—Cu1—N3—C255.88 (18)O15—Cu1—N7—C14i14.68 (10)
N10—Cu1—N3—C2171.06 (18)C6—N7—C8—C9149.50 (14)
N7—Cu1—N3—C2143.93 (18)C14i—N7—C8—C983.99 (16)
O15—Cu1—N3—C242.19 (18)Cu1—N7—C8—C937.36 (16)
O16—Cu1—N3—C4146.60 (10)N7—C8—C9—N1053.50 (19)
N10—Cu1—N3—C431.4 (2)C8—C9—N10—C11164.23 (17)
N7—Cu1—N3—C413.59 (10)C8—C9—N10—C1275.5 (2)
O15—Cu1—N3—C4115.34 (11)C8—C9—N10—Cu141.39 (17)
C2—N3—C4—C50.49 (17)O16—Cu1—N10—C1164.10 (17)
Cu1—N3—C4—C5164.56 (10)N3—Cu1—N10—C11179.40 (19)
C2—N3—C4—C6177.83 (13)N7—Cu1—N10—C11135.92 (17)
Cu1—N3—C4—C612.78 (16)O15—Cu1—N10—C1133.58 (17)
N3—C4—C5—N11.08 (17)O16—Cu1—N10—C1256.77 (13)
C6—C4—C5—N1177.73 (16)N3—Cu1—N10—C1258.5 (2)
N3—C4—C5—C14169.08 (15)N7—Cu1—N10—C12103.20 (13)
C6—C4—C5—C147.6 (3)O15—Cu1—N10—C12154.45 (13)
C2—N1—C5—C41.29 (17)O16—Cu1—N10—C9175.57 (12)
C2—N1—C5—C14169.39 (15)N3—Cu1—N10—C960.3 (2)
C5—C4—C6—N7133.00 (17)N7—Cu1—N10—C915.60 (12)
N3—C4—C6—N743.50 (16)O15—Cu1—N10—C986.75 (12)
C4—C6—N7—C8164.32 (12)C4—C5—C14—N7i101.86 (18)
C4—C6—N7—C14i68.75 (15)N1—C5—C14—N7i66.51 (19)
C4—C6—N7—Cu149.27 (12)N3—Cu1—O16—C1790.76 (18)
O16—Cu1—N7—C873.83 (19)N10—Cu1—O16—C17106.35 (18)
N3—Cu1—N7—C8154.43 (11)N7—Cu1—O16—C17169.17 (15)
N10—Cu1—N7—C812.25 (11)O15—Cu1—O16—C179.35 (18)
O15—Cu1—N7—C8107.68 (11)Cu1—O16—C17—O1817.6 (3)
O16—Cu1—N7—C645.21 (19)Cu1—O16—C17—C19162.04 (16)
Symmetry code: (i) x+3/2, y+1/2, z.
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
O15—H152···O160.91 (3)2.78 (3)3.1430 (19)105 (2)
O15—H152···O180.91 (3)1.86 (3)2.726 (2)158 (3)
O24—H241···O230.68 (3)2.03 (3)2.708 (2)171 (4)
N1—H1A···O23ii0.861.852.6866 (19)165
O15—H151···O22iii0.77 (3)1.95 (3)2.711 (2)168 (3)
O24—H242···O180.85 (3)1.95 (3)2.802 (2)177 (3)
O25—H251···O240.78 (4)2.05 (4)2.820 (3)172 (4)
O25—H252···O26iv0.83 (4)1.95 (4)2.776 (3)173 (4)
O26—H261···O240.71 (4)2.15 (4)2.848 (3)168 (5)
O26—H262···O25v0.82 (4)2.01 (5)2.806 (3)164 (4)
Symmetry codes: (ii) x+2, y+1, z; (iii) x+2, y, z; (iv) x+5/2, y1/2, z+1/2; (v) x, y+1, z.
 

Subscribe to Acta Crystallographica Section E: Crystallographic Communications

The full text of this article is available to subscribers to the journal.

If you have already registered and are using a computer listed in your registration details, please email support@iucr.org for assistance.

Buy online

You may purchase this article in PDF and/or HTML formats. For purchasers in the European Community who do not have a VAT number, VAT will be added at the local rate. Payments to the IUCr are handled by WorldPay, who will accept payment by credit card in several currencies. To purchase the article, please complete the form below (fields marked * are required), and then click on `Continue'.
E-mail address* 
Repeat e-mail address* 
(for error checking) 

Format*   PDF (US $40)
   HTML (US $40)
   PDF+HTML (US $50)
In order for VAT to be shown for your country javascript needs to be enabled.

VAT number 
(non-UK EC countries only) 
Country* 
 

Terms and conditions of use
Contact us

Follow Acta Cryst. E
Sign up for e-alerts
Follow Acta Cryst. on Twitter
Follow us on facebook
Sign up for RSS feeds